If you've read the other article this is no news for you that the end of validation happens after the end of verification.
In fact, software validation a device is ensuring that it conforms to defined user needs and intended uses. In the light of this definition, verification is a part of the whole process of validation.
Before ensuring that it conforms to user needs, the functions of the device have to be:
- described with software requirements and architecture,
- implemented with code,
- and tested.
So the requirements and the architecture have to be validated before they're implemented. That's why there are reviews of requirements, general conception and detailed conception before verification. These reviews participate to the validation process.
When requirements and architecture are validated, the software is implemented and tested through verification.
However verification tests as they are required by the IEC 62304 standard are not enough. Specific tests, i.e. clinical tests or end-user tests in real conditions, can be done to validate the device. So yes, some activities of validation happen after verification.
Goals of validation
The goals of software validation are not purely technical, compared to those of verification. Validation shall answer these questions:
- Does software conform to its intended use?
- Is clinical use effective and efficient?
- Are risks mitigated?
- Is the risk / benefit ratio favorable?
- Are the requirements enforced by national regulations met?
Knowing these goals, it's easy to see that pure technical tests done on a tests platform are not enough.
Who does Validation tests
Since software validation are not pure technical tests, it's the role of physicians, people with clinical knowledge to do validation tests. For this reason, validation tests are done in real environment, i.e. in healthcare centers.
Software teams don't do validation tests but they support them. If there is a bug a problem with software validation , it's the role of software developers to find out what's wrong. And fix it!